Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in the present disclosure and are not admitted to be prior art by inclusion in this section.
A functional block may selectively require power that is supplied at different voltage levels. As an example, during a first time period, the functional block requires power at a first voltage level; and during a second time period, the functional block requires power at a second voltage level different from the first voltage level. Selectively supplying power to the functional block may be achieved using switches that govern power supply from different power sources operating at respectively different voltage levels. However, it may not be possible to fully turn on and/or fully turn off conventional switches during operation, particularly when the voltage of the first power source is different from the voltage of the second power source.